The present invention, in some embodiments thereof, relates to a method for delivering medications to bodily orifices and, more particularly, but not exclusively, to a method for delivering drugs to the anal sphincter and/or anal canal.
Delivery of drugs presents a host of difficulties. Many medications cannot be taken orally, due to inherent instability or an inability to cross through the blood barrier in the intestines. Other drugs become highly diluted when circulating in the blood and thus give less response than desired. Other drugs, immediately after absorption from the intestine, get to the liver, where they start undergoing metabolism and degradation even before reaching the desired site of action. Additionally, drugs that enter the bloodstream inherently introduce the possibility of side-reactions, some of which can be debilitating or dangerous.
Bodily orifices, such as nose, ear, rectum, and vagina, offer the possibility of delivering a medical agent directly to the site of treatment. Suppositories, tampons, vaginal implants, sprays, drops and other elements are routinely used to bring medications directly to the site of need and to avoid liver metabolism. Typically, medication is released in a site-specific manner, with a concomitant increased concentration of pharmaceutical agent at the immediate site of medical need.
U.S. Pat. No. 5,413,793 teaches a multiphase pharmaceutical composition for combating an anorectal disease, in which a first phase contains an active ingredient and a second phase provides a layer of silicone oil to cover the treatment area, to repel water therefrom, so protecting the area from erosion by aqueous media. The composition is in the form of a suppository, which may be provided in any standard suppository base.
U.S. Pat. No. 5,215,758 teaches the controlled release of therapeutically active agents that is achieved from a controlled release matrix of sodium alginate and a calcium salt. When the composition is administered rectally, the matrix is combined with a therapeutically active agent and a suitable suppository base.
U.S. Pat. No. 5,023,082 teaches biodegradable sustained-release compositions capable of achieving the sustained release of a pharmaceutical or other agent. The compositions can be formed into implant devices which may be used to treat a wide variety of diseases and conditions. The implants are useful in treating diseases such as vaginal and periodontal disease which require prolonged drug release.
European Patent EP 0297725 describes a dispenser for dispensing a beneficial agent in an environment of use. The dispenser includes a wall surrounding a lumen comprising a matrix that includes a beneficial agent, means for pushing the matrix to an opening at one end of the dispenser, and means at the end of the dispenser for dispersing the matrix into a body cavity.
PCT Patent publication WO 2007/077551 teaches a rectally-insertable device for delivery of a pharmaceutical agent to the anal sphincter. The device includes a shell, a lower portion of which is placed proximate the anal sphincter, such that after insertion of device into the rectum, pharmaceutical agent in the shell is released in the vicinity of the anal sphincter.
European Patent EP 0293066 teaches a dispenser including a semipermeable membrane surrounding a lumen that includes a matrix having a pharmaceutical agent. The lumen includes a “push member” for urging the displaceable matrix from the dispenser. The “mouth” of the dispenser has a cross-sectional area similar to that of the body of the lumen from which the pharmaceutical agent is released.
British Patent GB 2,178,659 describes a device for delivering a beneficial agent, including a wall which defines an internal space that includes a heat-responsive agent, a drug, an “expandable means” (hydrogel or the like), and an exit means for the release of the drug composition from the device.
U.S. Pat. No. 4,292,300 teaches a non-dissolving suppository made essentially of methyl cellulose that includes a water-soluble therapeutic agent for release to the body through rectal insertion of the suppository.
U.S. Pat. No. 5,085,650 teaches a gynecological urethral suppository including a shaft, a bulbous head secured to one end of the shaft and a conical tail secured to the other end. The head comprises an outwardly curved retention surface and a gradually inwardly curved insertion surface. The tail includes an outwardly tapered retaining surface and a flat base, and has a maximum diameter that is greater than the maximum diameter of the head. The structure of the urethral suppository facilitates retention of the urethral suppository in the uretha such that medicament may be topically applied to the urethra, the urethral meatus, the bladder trigone, the bladder itself, and the ureters in an effort to cure urethral syndrome, trigonitis and posterior urethritis.
U.S. Pat. No. 5,860,946 teaches an instrument for inserting a suppository, wherein the instrument comprises a tubular housing with a first end adapted to receive the suppository between two tongues and a second end through which a plunger is inserted in the tube, which plunger has a first end having a circular cross section and two axially spaced circumferential flanges and a second end projecting from the second end of the tube. The first end of the tube has an inwardly extending shoulder which engages between the flanges and the first end of the piston is by radial slots divided into an uneven number of sectors. The plunger has between its first end and a press button at its second end angular spaced radial walls abutting the inner wall of the tube and axial spaced disc shaped walls are provided having a diameter corresponding to the inner diameter of the tube.